BLOG: May Warmth, Weekend Outlook, Summer Preview

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Happy Friday! Been a while since I have done a blog post but the weather hasn't been all that "interesting" lately. The warmth remains the big story. The first week of May has featured above average temperatures every single day. calanderHow does this stack up against other warm starts to May? Somewhat surprisingly, we have had much warmer starts to the month. Even some recent years on this list:may1to7I'll talk about the longer-range outlook later in the post, but if you've watched my videos and TV forecasts you know I am expecting the warmer-than-average weather to continue for much of the month.In the near term, it's Mother's Day weekend and lots of people will be outdoors. Today's threat of rain is very low, in the 10-20% chance range this afternoon. It will be so warm (and somewhat humid) that the atmosphere might try to pop a couple of showers.hrrrInstability will be pretty modest today so thunder isn't very likely in any of these stray showers. CAPE, or Convective Available Potential Energy is one of the ways we measure instability in the lower atmosphere. CAPE values today are pretty low:CAPETODAYOn Saturday, the atmosphere will be somewhat more unstable. This might lead to more numerous showers/storms in the afternoon but the coverage will still not be very high. Very very "hit or miss". Most will miss.sat5pSunday's weather map will be a wild one with strong low pressure across the Plains, severe weather possible again in the Midwest and Mississippi Valley, SNOW in the northern Plains and Subtropical Storm Ana still annoying the Carolinas.sunsfcHere at home, expect another very steamy day. Chance for a pop-up shower or storm is there once again in the afternoon but the coverage will still be pretty low. Keep those outdoor plans.A cold front will arrive Monday night. Behind that front, it WILL cool down and turn less humid.But for how long? Not long! Check out how quickly the warmth is likely to return:gefsClimate models have been leaning toward a June that will likely be closer to average than this very warm May. Notice the lack of any strong warm or cool signals for us:cfstempsWhat about the Summer as a whole? If the current modeling is on the right track...."ho hum". No strong signals for temperatures and precipitation at this point. Might end up being very "typical" in both departments.SUMMERcfsprecipThanks for reading and have a good weekend!Eric

BLOG: Severe Weather Threat Today; Quick Long-Range Peek

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Good morning everyone,Hope you enjoyed the warm weekend. Today will be the last balmy day for a while. The transition from the May Preview to more of a late-March pattern will be marked by some showers and thunderstorms today into tonight. Will the ingredients come together for some big storms and perhaps even severe weather?The setup: A cold front is marching east this morning and can easily be picked out on the surface map:nowAhead of the front, it is warm but not super humid. Dewpoints are in the 50s in most places.dewAs the front pushes east and some sunshine heats the air mass up, the atmosphere over the region will grow moderately unstable. Have a look at the CAPE, (Convective Available Potential Energy) which is a measure of how unstable the air mass is, at 2pm:CAPEA few/several hundred J/KG of CAPE is certainly enough for thunder and some "strong" storms but it's hard to get "severe" weather with CAPE values that low.Another thing we look at is something called "helicity", which measures the atmosphere's ability to produce rotating storms. It is not very high locally so the threat for a tornado is very very small.helicityThat said, there is a fair amount of wind energy above our heads and any stronger shower or storm could bring some of that down to the ground. Winds at 5,000 feet will be around 40-50 mph early this afternoon:850So we are looking at some showers and thunderstorms getting going during the midday and early afternoon. The 2pm simulated radar off our highest-resolution model shows this:2pmIf we are going to get some heavy storms today it looks like 1-4pm is our best window. By 5pm, the threat has shifted east, and the threat for severe weather is certainly higher in that direction.5pmThe Storm Prediction Center odds of large hail are low but not zero around the Valley today. Higher odds east.HAILODDSThreat for damaging winds is on the low end of the scale as well but overall is probably the more likely threat from any heavy storms today.WINDODDSAs always, we will keep you updated on TV and online as we navigate the day today. A quick reminder of the difference between watches/warnings/etc:severe-weather-awareness1OK, once we are done with today, it's not a very late-April like forecast for a while. Why? Well an area of low pressure in the upper levels is going to get bogged down for a while around the northern Great Lakes and SE Canada. This will prevent any sort of warmth from gaining a foothold and will steer chilly Canadian air south.jetthursjetsundayWe may start to emerge from that pattern by the middle of next week as the atmosphere gets "unclogged". jetwedsLong-range modeling shows a better pattern emerging by early May. The pattern may not produce temperatures as warm as we have seen recently, but it should be milder than the next 7-8 will be.16dayThanks for reading!Eric